These maps show forest canopy heights throughout the Earth and the United States. The data was obtained from NASA’s ICESat, Terra, and Aqua satellites and processed by Michael Lefsky. The shades of green show the height of the forest canopy from 0 to 230 feet. For any patch of forest, the height shown means that 90 percent or more of the trees in the patch are that tall or taller.

More information about the maps and the data can be found at the websites below:

There are two maps available. The first shows the forest height over the entire globe. The second is a more detailed map of the forest height for the United States. There is also a Google Earth version of the global map that can be downloaded using the button below.

Image Credit: NASA Earth Observatory/Image by Jesse Allen and Robert Simmon/Based on data from Michael Lefsky.

The Geologic Map of North America was published in 2005 by John C. Reed, Jr. (USGS), John O. Wheeler (Geological Survey of Canada), and Brian E. Tucholke (Woods Hole Oceanographic Institution). This is an amazing piece of work that covers the entire continent of North America at a scale of 1:5,000,000. The map distinguishes 939 geologic units, including 142 that are offshore. The map also depicts many geologic features including volcanoes, calderas, impact structures, axes of submarine canyons, spreading centers, transform faults, magnetic isochrons, and subduction zones. There are several websites that make the map and associated GIS data files available online.

Unfortunately, none of the websites provide a truly simple way for a layperson to view the map instantly online, and I will try to bridge that gap by converting into several different formats that will make it much easier for anyone with a web browser and/or Google Earth to view the map online.

I have also created modified versions of the map that will provide a different perspective than is possible with the original map. These include two versions of the map that add 3D hill shading using elevation data from NASA. The hill shading shows the relationship between topography and geology in such a way that is not possible by looking at the flat version of the map. I also created a version based on the Winkel Tripel Projection that provides a slightly different perspective.

The various versions of the map are available below.

Google Earth Versions

There are two versions of the map which can be viewed in Google Earth. The first version is the original flat map. The second version has the 3D hill shading added. Just click on the button below to open up the maps with Google Earth.

Zoom.it Versions

Zoom.it is a Microsoft Labs website that makes it very simple to view huge images online and works great for displaying high resolution maps such as these. I have created three versions of the Geologic Map of North America which can be viewed with Zoom.it. Simply navigate around the maps below using your mouse. Click on the icon in the lower right corner to view the map in full screen mode.

The first version is the original map.

The next version has 3-D hill shading added.

The final version is reprojected to Winkel Tripel Projection, which shows the map in a slightly different perspective. This version also has the 3-D hill shading.

I stumbled across a new (to me anyways) website from Microsoft Live Labs called SeaDragon which will process huge image files and make them available in such a way that they can easily be viewed online.

So far I have been able to get it to process a map as large as 1.4 gigapixels. SeaDragon even hosts the image tiles for free. Kudos to Microsoft Live Labs on this one, I’m impressed. Unfortunately there is no way to view the maps in Google Earth or Google Maps.

Below is a 1.4 gigapixel terrain map of the United States in Albers Projection that I created using a texture map from NASA with hill shading added from SRTM and GTOPO elevation data.

Don’t forget to click on the little icon in the bottom right corner to view it in full-screen mode.

**UPDATE 8/13/2011** – I have made a couple important updates. First, I have released a global version of the very popular 90-meter terrain map. I have also relaxed the licensing restrictions to allow for commercial use. See below for more details on both of these changes.

There are many ways to visualize the terrain and topography of the Earth’s surface on a map. Recent technological advances allow us to see the Earth’s surface in ways that have never been possible before. The terrain maps presented below were created with a desktop computer by combining over 150 gigabytes of elevation and imagery data from the sources listed below.

The resulting terrain maps show an amazing level of detail and allow us to see the surface of the Earth in a way that is not possible by viewing any of the source data sets on their own. In short, the SRTM and GTOPO elevation data was used to add hill shading to the Blue Marble imagery. The links below will allow you to download maps for various parts of the world. Quick warning, that the maps are very high resolution and some of them are very large downloads.

I’ve also decided to ease my licensing limitation a bit and release the Global Terrain Maps under the Creative Commons Attribution license. Please credit the Google Earth Library and provide a hyperlink to http://www.gelib.com/global-terrain-map.htm with any online reuse or distribution of this map. In addition, you must include a citation of “ASTER GDEM is a product of METI and NASA” somewhere near the Version 2 map. Additional suggested citations and detailed copyright information are included in the readme.txt file that can be found in the folder containing the map tiles. The credit and citations can go in the end-credits for multimedia presentations.

The Deepwater Horizon drilling platform exploded and sank on April 20, 2010 approximately 50 miles southeast of Venice, Louisiana. The resulting oil spill is slowly making its way northward toward the Louisiana coastline.

This collection of Google Earth overlays contains the following data sets:

High resolution Satellite Imagery of the oil spill area beginning April 21.

24-hour and 72-hour projected trajectory of the oil slick. The trajectory maps also show locations where oil is anticipated to be found on beaches and the predicted density of the oil slick.

Data from the USEPA ASPECT Project, which includes low altitude vertical, Infrared, and oblique aerial photographs, videos, and other data from the affected areas.

Index of aerial photographs from NOAA, USGS, NASA, and others. The indices can be viewed in Google Earth. The aerial photographs can be downloaded via links in the pop up balloons.

Data layers from Louisiana Governors Office of Homeland Security and Emergency Response. These include current and historic spill maps, Closure areas, Wildlife information, Environmentally sensitive areas, and points of interest.

Ecosystems of the Gulf of Mexico – Map from USGS GAP, LandFire showing the locations of Terrestrial Ecosystems in the affected area. (Here is the Legend)

Note that satellite imagery may not show the entire oil slick. Various factors, such as the time of day, presence of clouds, and the angle between the satellite and the water surface can affect the visibility of the oil slick significantly.

Also, Here is a PDF file containing some amazing high resolution photographs taken during the fire.

I will try to add to the collection in the coming days. If you find any other good sources of maps/data, please post a comment and I will try to add it to the collection.

The Clean Earth overlays replace the default Google Earth textures at high altitudes for the entire Earth. Instead of seeing inconsistent strips of different aerial/satellite photography that look very unrealistic, you can now see a nice clean natural looking Earth surface. The Clean Earth overlays use hill shading to exaggerate the vertical elevations of the Earth’s surface, which highlights hills, valleys and mountains much more than is possible with the default Google Earth surface. As you zoom in close to the Earth, the Clean Earth overlays will automatically fade away, allowing the default Google Earth surface to become visible.

The Clean Earth textures were created by combining NASA’s Blue Marble textures with global elevation/bathymetric data created by the Scripps Institution of Oceanography, which is derived from from the Space Shuttle’s SRTM mission and other sources.

There are two versions of the Clean Earth overlays. The High Resolution version provides a much greater level of detail and will be visible at lower altitudes than the Low Resolution version. The Low Resolution version (on by default) has less detail, but will load much faster, especially on older machines with slower internet connections.

I will also be adding Ultra-High resolution textures to certain areas of the Earth that will be based on much more detailed elevation data. If you have any suggestions for areas that would be interesting to see in Ultra-High detail, post a comment.

A magnitude 7.2 earthquake occurred at 3:40:40 p.m. (local time at the epicenter) on Sunday, 4 April 2010 in Baja California, approximately 75 km south of the Mexico-USA border (or about 100 miles east southeast of San Diego, California). The earthquake occurred at shallow depth (approximately 10 km) along the boundary zone between the North American and Pacific plates.

This Google Earth map overlay shows the earthquake intensity data from the USGS Shake Map but has been displayed on a much higher resolution terrain map (see this post for more information on the terrain base map). The red shaded areas are where the earthquake was the strongest. A more technical explanation can be found at the USGS website. Also included is an option to overlay the contours of the Peak Ground Acceleration (% g) values.

The file is about 5 megabytes and may take a minute or two to download.

This terrain map of California was created by combining the NASA Blue Marble imagery with the global elevation data from the Space Shuttle Radar Topography Mission (SRTM). The combination of these two data sets creates an amazing new way of viewing the Earth’s topography and landforms.

The SRTM elevation data is detailed enough that you can make out objects as small as freeways and levees and the Blue Marble imagery brings it all to life.

A 1,200 dpi GeoPDF file (53 megabytes) which also includes line/polygon overlays of State Parks, Lakes, Urban Areas and Major Roads for the entire state. These overlays can be turned on/off using the Layers feature of Acrobat.

In case you’re wondering “What about the rest of the Earth?”……I’m working on it. I’m hoping to have an global overlay at this detail in Google Earth within the next few weeks, but my lowly 6-year old single-core Pentium 4 takes its sweet time in processing the imagery.

I’m also thinking of doing individual maps of various states/countries in GeoPDF/GeoTIFF format since these would make nice base maps that can be used for many different purposes.